CVE-2020-24240: GNU Bison before 3.7.1 has a use-after-free in _obstack_free in lib/obstack.c (called from gram_lex) when a '\0' byte is encountered. NOTE: there is a risk…

PriorityP419medium5.5CVSS 3.1

AVLACLPRNUIRSUCNINAH

EPSS

1.26%

67.7th percentile

GNU Bison before 3.7.1 has a use-after-free in _obstack_free in lib/obstack.c (called from gram_lex) when a '\0' byte is encountered. NOTE: there is a risk only if Bison is used with untrusted input, and the observed bug happens to cause unsafe behavior with a specific compiler/architecture. The bug report was intended to show that a crash may occur in Bison itself, not that a crash may occur in code that is generated by Bison.

Affected

6 ranges

Vendor	Product	Version range	Fixed in
debian	bison	< bison 2:3.7.2+dfsg-1 (bookworm)	bison 2:3.7.2+dfsg-1 (bookworm)
gnu	bison	—	—
gnu	bison	>= 0 < 2:3.7.2+dfsg-1	2:3.7.2+dfsg-1
gnu	bison	>= 0 < 2:3.7.2+dfsg-1	2:3.7.2+dfsg-1
gnu	bison	>= 0 < 2:3.7.2+dfsg-1	2:3.7.2+dfsg-1
gnu	bison	>= 0 < 2:3.7.2+dfsg-1	2:3.7.2+dfsg-1

CVSS provenance

nvdv3.15.5MEDIUMCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H

nvdv2.07.1HIGHAV:N/AC:M/Au:N/C:N/I:N/A:C

osv5.5MEDIUM

vendor_debian5.5LOW

vendor_redhat5.5MEDIUM

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